Various types of sliding door or window assemblies are well known in the art. For example, a typical sliding door assembly may be used in a residential setting such as for a patio door. Such sliding door assemblies typically include two door sashes mounted within a master frame. One door sash may be stationary or remain in a fixed position relative to the master frame. The other door sash may typically be slidably mounted within the master frame. Alternatively, one or both of the door sashes can be hingedly connected to the master frame to be swinging doors.
A variety of types of locking mechanisms have typically been provided for these sliding door assemblies. A simple single point lock mechanism has been provided that includes a finger that engages a keeper on the door frame, holding the door in a closed position. This type of lock is simple to manufacture and simple to operate. However, it provides only a limited measure of security and can be relatively easily overcome in a forcible entry.
Multipoint lock assemblies are also known in the art. Typically, these assemblies include a plurality of keepers mounted to the frame. They also include a lock unit that mounts to an edge of the sliding door sash. The lock unit includes a corresponding plurality of latch members and a latch actuation unit. When the door is closed, the latch actuation unit is used to cause the latch members to engage the keepers, thereby preventing the door from being opened.
A disadvantage of known multipoint lock assemblies is that they are often complicated making them expensive and difficult to manufacture. They often include complicated lock actuators, latches and keepers. They also typically include complicated link mechanisms between moving parts along their lengths.
A further disadvantage is that multipoint lock assemblies require precise alignment between each keeper and its corresponding latch member. This alignment must be made at the time of installation and maintained through the life of the lock assembly. If proper alignment is not achieved or maintained, the lock assembly will not function properly. Misalignment may result in an inability of the latch mechanisms to engage the keepers or to be placed and maintained in a positively locked position. Misalignment may also result in damage to the latches or other components
A further disadvantage is that past lock units have been able to be activated while the door is in an open position. This places the latches in an engaged position while the latches are at a distance from the keepers. If the door is then closed before moving the latches back to an open or unlocked position, damage can result to the keepers, the latches or other aspects of the lock unit.
A further disadvantage is that typical multipoint lock units and their actuators cannot accommodate for misalignment that may occur over the course of time throughout the life of the unit.
A further disadvantage is that the latch members of the lock units are not typically as sturdy or strong as one would desire to ensure an appropriate measure of security.
The present invention is provided to solve these and other problems.